Oil or gas burner



June 26, 1933. R Z HOPKINS ET AL 1,914,567

OIL OR GAS BURNER Original Filed May 26, 1928 5 Sheets-Sheet l 1% enqra: $351 K/ZZor/zeys,

June 20, 1933. R. Z, PKINS ET AL 1,914,567

OIL OR GAS BURNER Original Filed May 26, 1928 3 Sheets-Sheet 2 g 4 l7 3izkuufxzfqrsv 3 5;

June 20, 1933. R. z. HOPKINS ET AL 1,914,567

OIL OR GAS BURNER Original Filed May 26, 1928 3 Sheets-Sheet 3 y 3y W(15% @s xzb wu,

Patented June 20, 1933 reuse? ear a RALrn' z norkinsnitnnnr nrnttiin's,AND HARLEY n. RAYMOND, or nnraorr, MICHIGAN, ASSIGNORS TO HUDSON MOTORcan COMPANY, OF DETROIT, MICHIGAN,

A OORCPORAT'ION or MiOH'IeAN OIL on. Gas BURNER Original applicationfiled Ma 26, 1928, sea-m1 no. 280,764. n'iviae'a and this applicationfiled A ia 1,

1930. Serial This invention relates to burners or heaters especially,although not exclusively, adapted for use in connection with drawingfurnaces or the like of the type disclosed and claimed in our priorapplication Serial No. 280,764, filed May 26, 1928,11OW Patent No.1,841,583, issued January 19,1932, of which this case is a division.

The invention has for an object to provide a burner or heater having acombustion chamber structure of such character as to permit the use ofeither liquid or gaseous fuel.

Another object of the invention is to provide'a heater or burner unit soconstructed as to'be readily detachable from the remainder of thefurnace or Oven structure and of a portablecharactenso as'tobe readilyreplaceable by another spare unit, thereby permitting relining and othernecessary repairs without shutting down the whole plant, said burnerunit being so organized as to permit the'ready' and convenient renewalof the combustion' chamber linin A further object of the invention is toprovide a' burn'er unit having provision for the cir'culationof airtherethr'ough to and from the oven, whereby the heat may be fully andefficiently utilized, but in'whichthe burner is at the same timeadequately cooled.

The foregoing and other objects of the invention, together with meanswhereby the latter may becarried into effect, will best be understoodfrom the following description of a preferred construction thereofillustrated in the accompanying drawings. It will also be understood,however, that the particular construction andarrangement described andshown'have been chosen for purposes of e:- emplification merely, andthat'said invention, as defined'by the claims hereunto appended, may beotherwiseembodied Without departure from the spirit and scope thereof.

In said drawings,

Fig. 1 is 'a'diagrammatic plan view of the complete furnace showing therelation of the heater or burner to the oven.

Fig. 2 is an end elevation looking from the inlet end ofth'eoven, orfrom the left in Fig. 3-is a transverse vertical section, taken Theapparatus as a whole includes an oven or tunnel unit, generallyindicated at A in Flgs. 1 and 2, a separate heater or burner unit,generally indicated at B, and detachable conduit connections, generallyindicated at C, whereby the hot products of combustion in the burnerunit B, together with a. certain amount of air heated thereby, may becirculated in a substantially closed circuit through said units.

The provision of a separate detachable burner unit B for the drawingoven makes it possible to employ a spare burner unit, so

that it is unnecessary, in case relining or other.

repairs are required in the heater, to shut down the entire plant. Onthe contrary, by disconnecting the conduit connections C, as hereinaftermore fully described, the disabled heater may be removed and replaced bya spare heater, whereupon the necessary repairs can be made at leisurewhile the furnace continues in operation. In order to facilitat-ethis,the burner or heater unit is. supportedin elevated positionby an openframe work comprising transverse structural niem bcrs and legs 21providing a space he neath the burner unit proper to receive theplatform of an industrial truck which, when rep Jirs are needed, may berun under the unit to lift and. carry thesame away and in a similarmanner to replace it by the spare unit.

As shown in Fig. 3, longitudinal angle iron bars 200 are mounted at eachside of the frame along the underside of the members 20, these barshaving vertical flanges acting as guides for the truck platform L wheninserted beneath the members 20. The bars 200 also have inwardlyextending horizontal flanges adapted to overlie the truck platform L andreceive the upperthrust thereof-when frame members 20 are riveted orotherwise circulated through the oven.

permanently secured, said casing having a fire brick lining 23 andenclosing a circulation chamber 24. At one end the casing 22 is providedwith an opening to receive a thimble 25 removably seated therein, saidthimble comprising spaced co-axial inner and outer members or walls 27and 28 connected by bolts 26. l ithin the circulation chamber 24 is acombustion tube or tubular combustion chamber 29 carried by fire bricksupports 30 within said circulation chamber and spaced from the walls ofthe latter by crossed angle bars 31. The combustion tube 29 communicatesat one end, as shown at 32, with the circulation chamber 24 and at itsopposite end is enclosed by the inner member 27 of the thimble Saidcombustion tube is of relatively small diameter in proportion to itslength and has relatively thin section walls composed of separate blocksor tiles of highly refractory material, such. as a suitable carborundumcomposition.

Supported by the thimhle 25 in alinement with the combustion chamber 29,so as to direct its flame into the latter through a suitable Venturibushing 33 of refractory material, is a burner proper, generallyindicated at D, said burner being of any approved and suitable typecapable of employing either oil or gas as a fuel. It will, of course, beunderstood that the air necessary to support combustion is supplied toor about the burner and enters the mouth of the bushing 33 with thefuel.

The space 34 between the inner and outer members of the thimble 25communicates with the circulation chamber 24 around the combustion tube29 immediately adjacent the burner end of said tube and alsocommunicates, outside the casing, with the outer air through suitableair inlets 35 controlled by a manually rotatable ring damper 36, wherebythe amount of air admitted to the circulation chamber can be controlled.

The construction and arrangement of parts above described adapts theapparatus for use with either liquid or gaseous fuel. The long thinwalls of the combustion tube absorb the interior heat quickly andtransfer it quickly to the air in the circulation chamber by which saidcombustion tube is completely surrounded. The fresh air admitted throughthe space 34 around the burner cools the hottestend of the combustiontube. As a result, overheating of the combustion tube is effectuallyprevented and the heat thereof transferred to the air which, ashereinafter explained, is For efficient heating by gaseous fuel a longthin combustion chamber is required, whereas oil burning furnaces, asheretofore constructed, have required a larger combustion chamber toprevent overheating. permits the use of liquid fuel in a combustionchamber of the type required for the most Renewal of thecombustionchamber tiles can, when necesefficient use of gaseous fuel.

The present construction end 38 thereof to the circulation chamber 24adjacent the point of communication 32 of the combustion chamber 29therewith.

The supply conduit 42 includes a short section 44 communicating with thecirculation chamber 24 at the top of the latter through the lining 23thereof, a T-fitting 45 communicating with the section 44, a section 46connected at one end by a detachable coupling 47 with one branch of thefitting 45 and at its opposite end communicating with a r the inlet of ablower 48 supported on the top of the oven and driven by a suitablemotor 49 and a section 50 leading from the outlet of the blower 48 totwo branches 51 which communicate with the'interior of the tunnel Aadjacent the outlet end of the latter. The other branch of the T-fitting45 is connected by a detachable coupling 52 with a stack 53 supportedindependently of the burner unit, as by hangers 54 from the roof 55 ofthe building within which the furnace is housed. The fitting 45 isprovided with dampers 61 and 62 adapted to control communication betweensaid fitting and the conduit section 46 and stack 53 respectively.

The return conduit 43 includes two branches 56 communicating with theinterior of the tunnel adjacent the inlet end of the latter and twobranches 57 communicating with the circulation chamber 24, said branches57 being connected by detachable couplings 58 withbranches 59 with whichcommunicates a sectional trunk connection 60 leading from the branches56.

It will be seen that, by disconnecting the detachable couplings 47, 52and 58, the burner unit B, with the portions 44, 45 and 57 of theconduit connections, may be removed as above described and replaced by asubstitute unit having corresponding conduit portions.

It will now be seen that the system described provides for asubstantially closed circuit circulation induced by the blower 48, ofthe air and products of combustion through the heater unit and ovenunit, the

hot gases leaving the heater unit adjacent the burner or hottest part ofsaid unit, entering the oven unit adjacent the discharge end of thelatter, leaving said oven unit adjacent the inlet end, and returning tothe heater at the cooler end of the latter, being thereafter caused toflow about the combustion tube so as to hold down the temperature of thelatter and to be reheated thereby. By suitable regulation of the dampers36, 61 and 62, sullicient, but only sufficient, outside air is admittedto the system to maintain combustion and make up the losses from theoven in charging and discharging, as hereinafter described, therebyfully utilizing all heat units. In starting the furnace, the damper 61is closed and the damper 62 opened, thereby cutting off the oven anddirecting all products of combustion to the stack, until the burner unithas then become thoroughly heated. Thereafter, relative adjustment ofthe dampers 61 and 62 controls the proportion of gases circulatedthrough the oven or discharged from the stack. Such fresh air as isadmitted to the system, in addition to that directly supplied to theburner, is admitted through the space 3% of the thimble 25 immediatelyaround the burner end of the combustion tube so as to become immediatelyheated as well as serving to cool the hottest end of the tube as aboveexplained.

Having thus described our invention, we claim:

1. A heater for drawing furnaces and the like comprising a casing, acirculation chamber extending substantially the length of said casingand enclosed thereby, a long, thin walled combustion tube within saidcirculation chamber and surrounded thereby and having a lengthsubstantially that of said circulation chamber ano a diameter relativelysmall in proportion to its length, said combustion tube having a burnerat one end and communicating with said circulation chamber at its otherend, and means for admitting air to said circulation chamber surroundingsaid tube at the end of the latter adjacent said burner.

2. A heater for drawing furnaces and the like, comprising a casingenclosing a circulation chamber and having an opening at one end, aremovable thimble in said open ing, a burner c rried by said thimble,and a combustion tube supported Within said circulation chamber inalinemcnt with said burner and removable through said opening when saidthimble is removed.

A heater for drawing furnaces and the like, comprising a casingenclosing a circulation chamber and having an opening at one end, aremovable thimble in said opening, a burner carried by said thimble, anda combustion tube supported within said circulation chamber in alinementwith said burner and removable through said opening when said thimble isremoved, said thimble having air inlets opening into said circulationchamber around said combustion tube.

4. A heater for drawing furnaces and the like, comprising a casingenclosing a circulation chamber and having an opening at one end, aremovable thimble in said opening, a burner carried by said thimble,supports in said chamber, and a sectional combustion tube alined withsaid burner and comprising sections carried by said supports andremovable through said opening when said thimble is removed.

.5. A heater for drawing furnaces and the like, comprising a casingenclosing a circulation chamber and having an opening at one end, aremovable thimble in said opening a burner carried by said thimble,supports in said chamber, and a sectional combustion tube alined withsaid burner and cou'iprising sections carried by said supports and asection carried by said thimble, said sections being removable throughsaid opening when said thimble is removed.

6. A. heater for drawing furnaces and the like, comprising a casingenclosing a circulation chamber and having an opening at one end, athimble in said opening comprisspaced coaxial inner and outer members, acombustion tube supported at one end by said inner thimble member andcommunicating at the other with said chamber, a burner carried by saidthimble in alinement with said tube, the space between said thimblemembers communicating with said chamber around said tube and having airinlets outside said casing, and a damper for controlling said airinlets.

7. in a drawing furnace or the like, having an even, a heater having acirculation chamber for the products of combustion, a combustion chambercommunicating therewith, a burner for said combustion chamber, a thimblesurrounding said combustion chamber at the end adjacent said burner foradmitting air to said circulation chamber and for cooling saidcombustion chamber at the burner end, and conduits communicating withsaid circulation chamber adjacent the opposite ends thereof,respectively, whereby heated air may be circulated therethrough to andfrom the oven of said furnace.

8. In a drawing furnace or the like having an oven, a heater having acirculation chamber for the products of combustion, a combustion chambercommunicating therewith, a burner for said combustion chamber, a thimblesurrounding said combustion ch ainber at the end adjacent said burnerfor adi'nitting air to said circulation chamber and for cooling saidcombustion chamber at the burner end, and conduits communicating withsaid circulation chamber adjacent the opposite ends thereof,respectively, whereby heated air may be circulated therethrough to andfrom the oven of said furnace.

9. In a drawing furnace or the like having an oven, a heater having acirculation chambeer for the products of combustion, a combustionchamber surrounded by said circulation chamber and communicatingtherewith at one end, a burner at the opposite end of said combustionchamber, a thimble surrounding said combustion chamber at the endadjacent said burner for admitting air to said circulation chamber andfor cooling said combustion chamber at the burner end, a conduitcommunicating with said circulation chamber adjacent the burner end ofsaid combustion chamber, and a second conduit communicating with saidcirculation chamber adjacent the point of communication of saidcombustion chamber therewith, whereby heated air may be circulatedtherethrough to and from the oven of said furnace.

10. In a drawing furnace or the like having an oven, a heater having acirculation chamber for the products of combustion, a long, thin-walledcombustion tube of relatively small diameter in proportion to its lengthwithin said circulation chamber, said tube being surroundedby saidcirculation chamber and communicating therewith at one end, a burner atthe opposite end of said tube, a thimble surrounding said tube at theend adjacent said burner for admitting air to said circulation chamberand for cooling said tube at the burner end, a conduit communicatingwith said circulation chamber adjacent the burner end of said tube, andsecond conduit communicating with said circulation chamber adjacent thepoint of communication of said tube therewith, whereby heated air may becirculated therethrough to and from the oven of said furnace.

11. In a drawing furnace or the like having an oven, a heater having acirculation chamber for the products of combustion, a long, thin-walledcombustion tube of relatively small diameter in proportion to its lengthwithin said circulation chamber, said tube being siiirrounded by saidcirculation chamber and comnnmicating therewith at one end, a burner atthe opposite end of said tube, a thimble surrounding said tube at theend adjacent said burner for admitting air to said circulation chamberand for cooling said tube at the burner end, a conduit communieatingwith said circulation chamber adjacent the burner end of said tube, anda second conduit communicating with said circulation chamber adjacentthe point of communication of said tube therewith, whereby heated airmay be circulated therethrough to and from the oven of said furnace.

In testimony whereof we afiix our signatures. RALPH Z. HOPKINS.

ALBERT E. FELLERS. HARLEY D. RAYMOND.

